The present invention relates to a system for controlling the operation of an automotive engine, and more particularly to a learning control system for updating data stored in a table for the learning control. In the learning control system, the updating of data is performed with new data obtained during the steady state of engine operation. Accordingly, means for determining whether the engine operation is in steady state is necessary. A conventional learning control system has a matrix (two-dimensional lattice) comprising a plurality of divisions, each representing engine operating variables such as engine speed and engine load. When the variables continue for a predetermined period of time in one of the divisions, it is determined that the engine is in steady state. On the other hand, a three-dimensional look-up table is provided, in which a matrix coincides with the matrix for determining steady state. For such a three-dimensional table, a RAM having a large capacity must be provided.